Back-to-the-Future Plants Give Climate Change Insights
- Experiments exposing today’s seeds with future CO2 conditions can fairly accurately portray future plant response
- Plant growth is stimulated as CO2 increases, but drought and high temperatures can limit that growth
- Higher-carb crops expected under future climate change
Scientists from the University of California, Davis, and the University of Southampton in the United Kingdom examine that question in a study published today in the journal Global Change Biology. They found that specialized outdoor laboratories more closely resemble what happens in nature than was previously realized.
– Gail Taylor
The study authors compared plant responses at FACE facilities with plant responses across 11 naturally occurring, high-CO2 springs. Plants at these springs survive extremely high concentrations of carbon dioxide, up to 1,000 parts per million in some areas, for many years over multiple generations.
As an isolated factor, high CO2 concentrations are expected to result in more plant growth and continued global greening. Yet drought and high temperatures — both of which are expected to increase under future climate projections — can limit that growth.
“If plants are exposed to higher temperatures and drought, there will likely be negative impacts, overall, so it’s a tradeoff,” Taylor said. “But our analysis gives us confidence that plants are likely to keep responding positively to rising CO2 if no other climatic factors are limiting.”
With rising CO2, crop yields are expected to increase in northern latitudes but may decrease closer to the equator. California is expected to experience lower crop yields because of water limitations and high temperatures, while in Britain, impacts on crops will be variable.
Most of the FACE experiments have concentrated on commodity crops like soybeans, maize, wheat and rice. Specialty crops, like the nuts, fruits and vegetables grown in California, have not been studied in FACE facilities yet, but Taylor hopes to change that.
“The analysis shows that it’s possible to test new varieties of plants in FACE experiments before it is critical that they perform in the wider world,” Taylor said. “These ‘time-traveling’ plants that move forward and backwards across the decades can be extremely valuable in understanding how plants are likely to respond to the changes projected as a consequence of anthropogenic climate change.”
Additional authors include Jasmine Saban and Mark Chapman of the University of Southampton.
The study was supported by funding from the Natural Environment Research Council, UC Davis and the British Council.